Condylar and coronoid processes Most of the lateral surface provides attachment for the masseter muscle. The ramus of mandible is quadrangular in shape and has medial and lateral surfaces The superior border is notched to form the mandibular notch The coronoid process extends superiorly from the junction of the anterior and superior borders of the ramus. The posterior and inferior borders of the ramus intersect to form the angle of mandible provides attachment for temporalis muscle
The condylar process is made of: 1-the head of mandible, participates in forming the temporomandibular joint; and 2-the neck of mandible, which bears a shallow depression (the pterygoid fovea) on its anterior surface for attachment of the lateral pterygoid muscle.
The medial surface of the ramus of shows the following featuers: 1-Mandibular foramen, which is the superior opening ofthemandibular canal. The inferior alveolar nerve and vessels pass through this foramen. 2-A triangular elevation (the lingula) for attachment of the mandibular end of the sphenomandibular ligament 4-An elongate groove (the mylohyoid groove) extends anteroinferiorly from the mandibular foramen. The nerve to mylohyoid is in this groove 3-Roughened for attachment of the medial pterygoid muscle
Masseter muscle The masseter muscle is quadrangular in shape is Origin: inferior border and inner surface of the zygomatic arch. insertion: into the lateral surface of the ramus of the mandible and its coronoid process. The masseter is innervated by the masseteric nerve from the mandibular nerve [V3]
Temporalis muscle The temporalis muscle is a large fan-shaped muscle that fills much of the temporal fossa It originates from the bony surfaces of the temporal fossa superiorly to the inferior temporal line Tip and medial surface of the coronoid process And anterior border of the ramus of the mandible Temporalis is a powerful elevator of the mandible, closes the mandible Temporalis is innervated by deep temporal nerves that originate from the mandibular nerve
Medial pterygoid The medial pterygoid muscle is quadrangular in shape and has deep and superficial heads Origin: medial surface of the lateral plate of the pterygoid process and the pyramidal process of the palatine bone Insertion: medial surface of the ramus of mandible inferior to mandibular foramen The medial pterygoid is innervated by the nerve to medial pterygoid from the mandibular nerve [V3]. The medial pterygoid mainly elevates the mandible, closing jaws
Lateral pterygoid The lateral pterygoid is a thick triangular muscle The upper head originates from the roof of the infratemporal fossa (inferior surface of the greater wing of the sphenoid and the infratemporal crest The lower head is larger and originates from the lateral surface of the lateral plate of the pterygoid process Insertion: into the neck of mandible into the capsule of the Temporomandibular joint Into the articular disc. The lateral pterygoid is innervated by the nerve to lateral pterygoid from the mandibular nerve [V3].